1. Field of the Invention
This invention generally relates to an output circuit including an integrated circuit and more particularly to an output circuit including an integrated circuit, the high integration of which is realized by reducing power consumption thereof.
2. Description of the Related Art
A conventional output portion of an integrated circuit 1 is provided with a driving circuit which is composed of a PNP transistor 101 and an NPN transistor 102 as illustrated in FIG. 8 and drives the integrated circuit by supplying electric current from a positive electrode V.sub.o of a power source. An example of such a conventional output portion or circuit is disclosed in Japanese Patent Application Publication No. 1-33653 Official Gazette.
However, in case of the conventional output circuit provided with such a driving circuit consisting of the PNP transistor 101 and the NPN transistor 102, the emitter of the PNP transistor 101 is connected to the collector of the NPN transistor 102 and moreover the collector of the PNP transistor 101 is connected to the base of the NPN transistor 102 in the integrated circuit 1. Thus, in case where a large amount of electric current is supplied thereto, there is large power consumption in the NPN transistor 102. Consequently, the conventional output portion has a drawback that integration of multiple channels is restricted by heat radiation and power consumption depending on a package of an integrated circuit (IC), namely, that the number of channels cannot be increased in case of integration of multiple channels. The present invention is created to eliminate the above described drawback of the conventional output circuit of an integrated circuit.
It is, therefore, an object of the present invention to provide an output circuit of an IC which can reduce power consumed in the IC and achieve high packaging density of the IC and realize provision of multiple channels therein.